Magnetic Resonance Imaging

The use of MRI as a powerful imaging and characterization modality in pharmaceutical dissolution research is now well established [1]. The non-invasive and non-destructive nature of MRI enables the investigation of structural, chemical and dynamical processes in many optically opaque systems at the microscopic level. Spatial maps of water penetration, tablet swelling and dissolution, as well as the mobilization and distribution of drug products can now be quantified and visualized [2,3]. In addition, the hydrodynamics within a USP recommended flow-through dissolution apparatus can also be visualized by MRI [4]. Such comprehensive information is essential in pharmaceutical research for: (i) the correct interpretation of conventional drug dissolution profiles and (ii) the optimal design (QbD) of controlled release formulations.

Lipid-based drug delivery systems have become a popular approach for the delivery of poorly water-soluble drugs. The limitations associated with this formulation strategy have been the drug solubility in the delivery systems and the lack of characterization techniques predicting the in vivo performance. Solid state characterization of the in vitro digestion products has provided new insights that scrutinize current paradigms in the development of lipid-based drug delivery systems.

Formulation of co-amorphous drug systems

Using the amorphous form of a drug, instead of its crystalline counterpart is one way to enhance the bioavailability of poorly water-soluble drugs. However, in order to fully benefit from the solubility advantages of amorphous drugs, one needs to overcome phyisco-chemical limitations including poor physical stability associated with the amorphous form. Co-amorphous drug formulations are a novel and one of the most promising formulation approaches in this context, where the drug in its amorphous form is stabilized through strong intermolecular interactions with its co-amorphous low molecular weight partner molecule.